DNA methylation has been shown to be associated with cancer, inflammatory and metabolic disorders, neuronal plasticity and memory formation. Up to now, DNA methylation has been largely studied by whole genome bisulfite sequencing of populations of cells. Studies like the Epigenomics Project and the 1000 Genomes Projects have contributed significantly to our understanding of genetic, phenotypic and epigenetic variations amongst individuals in a population. However, all of these studies are essentially averaged snapshots or normalized fixed time assessments of our genetic and epigenetic makeup. Nowhere is it more important to study dynamic variation than in epigenomics. Almost all our understanding of the epigenome and its regulation has been derived from studies carried out at the population level - thousands of cells being sequenced together. There is considerable evidence indicating that cell to cell variability in gene expression is ubiquitous, even amongst 'homogeneous populations of cells. The extent of epigenetic heterogeneity in diverse cell types in tissues remains largely unknown. Our goal in this grant application is to develop a solution to this problem by developing at least two single cell methyl-sequencing library preparation protocols that will allow investigators to interrogate epigenetic modifications amongst individual cells of a population.